JP3480664B2 - Imaging device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus which outputs video signals of different signal forms by using one type of image pickup element.

[0002]

2. Description of the Related Art In recent years, high-definition video signals (hereinafter referred to as HD signals) and progressive video signals have been known as video signals developed for high definition and high image quality of TV broadcasting. Among these, the HD signal, that is,
Number of effective scanning lines is 1035, and interlace scanning is 1
035i, and equipment of this standard has been put into practical use.
Further, a progressive scan with 480 effective scanning lines is referred to as 480p, and these standards have received attention as a promising system in the next-generation digital TV broadcasting.

Under such circumstances, there is an increasing need for devices that simultaneously handle different types of video signals, and efficient operation can be expected by using shared devices as compared with the case of using dedicated devices for each. . Such a study has been made also in the image pickup apparatus, and for example, Japanese Patent Laid-Open No. 6-1650.
As described in Japanese Patent No. 38, No. 38, a method is proposed in which the driving method of the photoelectric conversion element is changed between sequential scanning and interlaced scanning so as to be compatible with both the NTSC system and the 480p scanning system.

[0004]

However, in the above-mentioned conventional image pickup apparatus, both the sequential scanning (480p) and the interlaced scanning (NTSC) are possible, but the number of scanning lines is doubled. Was limited to. That is, 103
It has been difficult to output video signals of signal forms such as 5i and 480p having completely different scanning lines.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide an image pickup apparatus which can be used for both progressive scanning and interlaced scanning of different signal forms.

[0006]

In order to solve the above-mentioned problems, the invention according to claim 1 of the present application generates a pixel signal using a two-dimensional CCD light receiving element, and interlace-scans or sequentially scans the pixel signal. In an image pickup device for converting into a scanning image signal, a pair for adding signal charges of two photoelectric conversion elements adjacent to each other in the vertical direction of the CCD light receiving element is changed for each field during interlaced scanning, and for sequential scanning. An image pickup unit that outputs a video signal of each horizontal scanning line fixedly, and an output of the image pickup unit as it is during interlaced scanning, and outputs the image signal of the image pickup unit during sequential scanning in the horizontal scanning direction and the vertical scanning direction. And converting means for extracting effective pixels and converting into a video signal of a predetermined signal form,
It is characterized by including.

According to a second aspect of the invention of the present application, in the image pickup apparatus according to the first aspect, the conversion means extracts the effective pixels while keeping the screen aspect ratio input from the image pickup means. It is a thing.

According to a third aspect of the present invention, in the image pickup apparatus according to the first or second aspect, the conversion means converts at least a horizontal scanning frequency and a vertical scanning frequency of a video signal at the time of sequential scanning. It is characterized by having means.

The invention according to claim 4 of the present application includes claims 1 to 1.
3. The image pickup device according to any one of 3 above, wherein the conversion means includes at least a sampling rate conversion means for converting a sampling rate of a video signal during sequential scanning.

The invention according to claim 5 of the present application includes claims 1 to 1.
4. In the image pickup apparatus according to any one of 4 above, the image pickup unit is configured so that the number of effective scanning lines in one field during interlaced scanning is
The number of effective scanning lines is greater than the number of effective scanning lines in one frame during sequential scanning.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, in a two-dimensional CCD light receiving element, the pair for adding the signal charges of two photoelectric conversion elements adjacent in the vertical direction is changed for each field during the interlaced scanning, and for the sequential scanning. Is fixed and includes image pickup means for outputting a video signal, and conversion means for extracting the output of the image pickup means by the effective pixels for sequential scanning and converting the output into a predetermined signal form. As a result, it is possible to output the video signals of the sequential scanning and the interlaced scanning of different signal forms.

An image pickup apparatus according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of the image pickup apparatus according to this embodiment.
This image pickup device is configured to include an image pickup means 1, an extraction means 2, a scanning frequency conversion means 3, a sampling rate conversion means 4, a video signal output terminal 5a, and a control signal input terminal 6. Further, the extracting means 2, the scanning frequency converting means 3, and the sampling rate converting means 4 constitute a converting means 5 for converting a predetermined signal form into a video signal of a target signal form.

A control signal input from the outside to the input terminal 6 is a signal for controlling whether the image pickup apparatus is operated as a sequential scan or an interlaced scan. Here, the 1035i signal is output from the output terminal 5a during the interlaced scanning operation, and the 480p signal is output from the output terminal 5b during the sequential scanning operation.

The image pickup means 1 comprises a two-dimensional charge coupled device (charge coupled device) as shown in FIG.
It is a solid-state image sensor having a CCD 7 which is ice), a transfer pulse generating means 8 and a signal processing section 9. The transfer pulse generating means 8 of FIG. 2 receives a control signal from the input terminal 6 and outputs a transfer pulse for interlaced scanning or sequential scanning to CC.
It is output to D7. The CCD 7 is an element that outputs an interlaced scanning or progressive scanning video signal by this transfer pulse. The pixel signal output from the CCD 7 is subjected to signal processing required by the image processing device in the signal processing unit 9, and is output from the output terminal 10.

FIG. 3 is a block diagram showing the outline of the CCD 7. In the figure, the light receiving portion 22 of the CCD 7 is provided with a large number of photoelectric conversion elements 20a to 20f and a plurality of vertical CCDs 21. The vertical CCDs 21 in each column are connected to a storage unit 23, and each storage unit 23 is connected to a horizontal CCD 24. The output terminal 25 is a terminal for outputting a pixel signal from the horizontal CCD 24. The input terminals 26 to 28 are input terminals for transfer pulses applied to the light receiving section 22, the storage section 23, and the horizontal CCD 24, respectively. Note that, in FIG. 3, the photoelectric conversion elements are illustrated with the number thereof omitted, and actually, the photoelectric conversion elements have a two-dimensional array configuration capable of outputting a 1035i signal.

Each of the photoelectric conversion elements 20a to 20 of the light receiving section 12
The signal charge generated at f is applied to the vertical CCD 21 and the storage unit 2.
3. The pixel signal (video signal) is output from the output terminal 25 via the horizontal CCD 24. At this time, the signal charges generated in the photoelectric conversion elements 20a to 20f are added by two vertically adjacent pairs and output from the vertical CCD 21. That is, a video signal of a horizontal scanning line corresponding to 1/2 of the number of photoelectric conversion elements 20 in the vertical direction is obtained every 1/60 second period.

During interlaced scanning, in the first field period, for example, a pair of photoelectric conversion elements 20a and 20b, a pair of photoelectric conversion elements 20c and 20d, and photoelectric conversion elements 20e and 2 are used.
Vertical pairing is performed such as 0f pair. Also,
In the second field period, the photoelectric conversion elements 20b, 20c
And the photoelectric conversion elements 20d and 20e are vertically paired. Therefore, the combination of vertical pairing changes for each field, and the interlaced scanning signal is output. Further, during the sequential scanning, the vertical pairing is not changed and is left fixed so that the sequential scanning signal is output.

This situation will be described with reference to the operation conceptual diagram of the CCD shown in FIG. FIG. 4 shows a part of the apparatus shown in FIG. 3 in a horizontal position. Here 1
One set of vertical CCDs 31 for the photoelectric conversion element group 30 in a row
Is provided.

First, the operation during interlaced scanning will be described. In the first field period, for example, in the odd field period, as shown in FIG. 4A, the signal charge from a certain photoelectric conversion element and the signal signal from the adjacent photoelectric conversion element are simultaneously transferred to the vertical CCD 31, and the vertical CCD 31. Add and read in. At this time, each electrode of the vertical CCD 31 (φ1
The voltage of the transfer pulse given to .phi.4) is given via the input terminal 26 so that .phi.4 becomes L (low) and the other becomes H (high) at a predetermined timing, for example.

Next, in the second field period, for example, the even field period, as shown in FIG. 4B, the pair of photoelectric conversion elements to be added is changed to obtain the interlaced scanning signal.
At this time, the voltage of the transfer pulse given to each electrode (φ1 to φ4) of the vertical CCD 31 is φ2 at a predetermined timing.
Is controlled to be L (low) and the other to H (high).

Next, the operation during sequential scanning will be described.
During sequential scanning, the pair of photoelectric conversion elements to be added is fixed. For example, the operation as shown in FIG. 4A is performed for all the frames to obtain a signal for progressive scanning.

Therefore, from the image pickup means 1 shown in FIG. 2, an interlaced scanning or progressive scanning video signal can be obtained depending on the type of the control signal given through the input terminal 6. However, the video signal from the image pickup means 1 depends on the number of photoelectric conversion elements. For example, when the 1035i signal is obtained as the interlaced scanning, the horizontal scanning line is 518 in the horizontal scanning.
It will be a book.

The conversion means 5 shown in FIG. 1, that is, the extraction means 2, the scanning frequency conversion means 3, and the sampling rate conversion means 4 generate a regular 480p signal from a video signal having 518 scanning lines during sequential scanning. It should be noted that the conversion means 5 is made to be through during the interlaced scanning.

Next, the operation of the conversion means 5 at the time of progressive scanning will be described. FIG. 5 is a conceptual diagram of the screen size for explaining the operation of this embodiment. The image pickup means 1 of FIG.
The video signal indicated by the size of the outer frame is output. That is, the number of scanning lines in the outer frame is 518, the number of horizontal samples is 1920, and the aspect ratio is Ya: Xa =
It is 16: 9.

When such a video signal is inputted to the extracting means 2, 480 horizontal scanning lines are extracted from 518 horizontal scanning lines. The extraction method may be to remove the signal of a predetermined horizontal scanning line. Here, although 480 horizontal scanning lines can be obtained, since the screen size also needs to be 16: 9, horizontal samples are also extracted. As a result, the video signal shown by the inner frame in FIG. 5 is obtained. In the horizontal sample, the aspect ratio Yb: Xb = 16: 9 is set to 1920 × (480 /
518) = 1779 samples are extracted.

The video signal in the inner frame of FIG. 5 is input to the scanning frequency conversion means 3. The scanning frequency conversion means 3 frequency-converts the video signals of 1779 samples in the horizontal direction and 480 in the vertical direction on the effective screen of one frame. That is, the scanning frequency conversion means 3 frequency-converts the video signal,
Including the blanking portion, the number of scanning lines is converted to 525 and the horizontal scanning frequency is converted to 31.5 kHz. The frequency conversion method can be realized, for example, by once storing the video signal in a memory or the like and changing the read timing from the write timing.

The output of the scanning frequency conversion means 3 is input to the sampling rate conversion means 4. The sampling rate conversion means 4 converts into a sampling frequency often used as a 480p signal. The 480p signal often samples the luminance signal at 27 MHz. Therefore, down-sampling is performed from 1779 samplings so that the effective horizontal sampling number becomes 720 samplings. That is, about 64.21 MHz (60 Hz × 525
X1779x2200 / 1920) sampling is converted to 27 MHz sampling by D / D conversion (digital-digital conversion). As a result, the sampling rate conversion means 4 outputs 480p having a regular rate.
The signal is obtained.

As described above, according to the present embodiment, it is possible to realize a scanning system of progressive scanning and interlaced scanning, and an image pickup apparatus which outputs video signals having different effective pixels. Further, according to the present embodiment, since the signal charges of the photoelectric conversion elements in the vertical direction are added in both sequential scanning and interlaced scanning, CC
The sensitivity of D can be made equal in both formulas.

When the 480p signal is output in analog, the output of the scanning frequency conversion means 3 may be DA-converted (digital-analog conversion) at a predetermined rate (for example, 64.21 MHz). Further, although the present embodiment has described the image pickup apparatus that can use both 1035i signal and 480p signal, it is also easy to use an image pickup apparatus that can use both interlaced scanning signals and 480p signals with 1080 effective scanning lines. is there.

Further, in the present embodiment, an example in which the conversion means 5 is converted in the procedure of the extraction means 2, the scanning frequency conversion means 3 and the sampling rate means 4 is shown, but the conversion procedure is not limited to this. Alternatively, another procedure may be used as long as a signal within a desired range is converted into a predetermined signal form.

[0031]

As described above, according to the present invention, the pairing method of the vertical photoelectric conversion elements in the CCD light receiving element is changed between the sequential scanning and the interlaced scanning, and further, the extracting means during the sequential scanning. By providing the scanning frequency conversion unit, the sampling rate conversion unit, and the like, it is possible to realize an image pickup apparatus that is used for both progressive scanning and interlaced scanning. Therefore, when generating video signals of different signal forms, it is not necessary to prepare a dedicated image pickup device for each, and it is possible to switch the image pickup devices as needed, so that it is possible to perform efficient shooting at a shooting site or the like.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an imaging device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an image pickup unit used in the image pickup apparatus according to the present embodiment.

FIG. 3 is a block diagram showing a configuration of a CCD used in the image pickup apparatus of this embodiment.

FIG. 4 is a conceptual diagram explaining the operation of the CCD in the present embodiment.

FIG. 5 is a conceptual diagram of a screen size for explaining the operation of the conversion means in the present embodiment.

[Explanation of symbols]

1 Imaging means 2 Extraction means 3 Scan frequency conversion means 4 Sampling rate conversion means 5 conversion means 5a, 5b, 10 output terminals 6,26,27,28 Input terminals 7 CCD 8 Transfer pulse generation means 9 Signal processing unit 20, 20a to 20f photoelectric conversion element 21 Vertical CCD 22 Light receiving part 23 Storage 24 horizontal CCD 30 Photoelectric conversion element group 31 Vertical CCD

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshio Sugimori 14-2, 2nd Town, Chiyoda-ku, Tokyo Japan Television Network Co., Ltd. (72) Inventor Akihiro Hori 14th-2, 2nd Town, Chiyoda-ku, Tokyo Japan Television Within Broadcasting Network Co., Ltd. (56) Reference JP-A-7-23300 (JP, A) JP-A-7-135592 (JP, A) JP-A-5-14821 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) H04N 5/335 H04N ^7/ 00-7/093

Claims (5)

(57) [Claims] 1. An imaging device for generating a pixel signal using a two-dimensional CCD light receiving element and converting the pixel signal into an interlaced scanning or progressive scanning video signal, which is adjacent to a vertical direction of the CCD light receiving element. An image pickup unit that changes the pair for adding the signal charges of the two photoelectric conversion elements for each field during interlaced scanning and fixes the image signal of each horizontal scanning line during sequential scanning, and the image capturing unit during interlaced scanning. A conversion means for outputting the output of the means as it is, extracting effective pixel portions in the horizontal scanning direction and the vertical scanning direction from the output video signal of the image pickup means during sequential scanning, and converting the video signals into a predetermined signal form. An image pickup apparatus comprising: 2. The conversion means extracts effective pixels while keeping the screen aspect ratio input from the imaging means.
The imaging device described. 3. The image pickup apparatus according to claim 1, wherein the conversion unit includes at least a scanning frequency conversion unit that converts a horizontal scanning frequency and a vertical scanning frequency of a video signal during sequential scanning. . 4. The image pickup apparatus according to claim 1, wherein the conversion unit includes at least a sampling rate conversion unit that converts a sampling rate of a video signal during sequential scanning. . 5. The image pickup means according to claim 1, wherein the number of effective scanning lines of one field during interlaced scanning is larger than the number of effective scanning lines of one frame during sequential scanning. The imaging device according to the item.